Lecture 14

Question 1

What are the three types of leishmaniasis?

Answer 1

1. Visceral leishmaniasis or kala-azar
2. Cutaneous leishmaniasis or oriental sore
3. Mucocutaneous leishmaniasis or espundia

Question 2

How is leishmaniasis transmitted?

Answer 2

Female sand flies (Phlebotomus and Lutzomyia spp)

Question 3

What disease does leishmaniasis have co-infection with?

Answer 3

HIV - especially from Europe - more serious

Question 4

Causative organisms

Answer 4

Complex genus
>20 species
Seen in Asia, Africa, Americas, Southern europe

Question 5

In leishmaniasis, what are motile and in sand flies

Answer 5

Promastigotes

Question 6

Main diagnostic stage of leishmaniasis

Answer 6

Amastigotes

Question 7

Epidemiology of leishmaniasis

Answer 7

350 million at risk in 98 countries

Visceral - 200-400K per year (fatal)

Cultaneous - 0.7-1.2 million per year (disfiguring)

Visceral fatal if untreated (95% fatality)
- Up to 30K deaths/year

90% of VL across 4 countries - India, Bangladesh, Brazil, Sudan

• Large number of asymptomatic cases
• Animal reservoirs

Question 8

Diagnosis of leishmaniasis

Answer 8

Indirect:
- Clinical - anaemia, leucopenia (low WBC), thrombocytopenia (low platelets)

DAT (direct aggutination test)
IFAT (indirect fluorescent antibody test)
ELISA (Enzyme linked immunosorbent assay)
ICT (immunochromatographic strip test)

Direct:
Parasitological
- Seeing amastigotes in aspirates from spleen, lymph nodes, bone marrow, or liver
- Promastigotes in cultures derived from aspirates

Antigen detection - KAtex urine test

PCR
NASBA (nucleic acid sequence-based assay

Question 9

Clinical diagnosis of visceral leishmaniasis

Answer 9

Incubation - 1-2 months to >10yrs

Phases include asymptomatic, subclinical, acute, chronic